import 'package:flutter/material.dart';
import 'package:razorpay_flutter/razorpay_flutter.dart';
import 'package:marco/helpers/services/payment_service.dart';
import 'package:marco/helpers/services/app_logger.dart';

class PaymentController with ChangeNotifier {
  final Razorpay _razorpay = Razorpay();
  final PaymentService _paymentService = PaymentService();

  bool isProcessing = false;
  BuildContext? _context; // For showing dialogs/snackbars

  PaymentController() {
    // Razorpay event listeners
    _razorpay.on(Razorpay.EVENT_PAYMENT_SUCCESS, _handlePaymentSuccess);
    _razorpay.on(Razorpay.EVENT_PAYMENT_ERROR, _handlePaymentError);
    _razorpay.on(Razorpay.EVENT_EXTERNAL_WALLET, _handleExternalWallet);
  }

  void disposeController() {
    _razorpay.clear();
  }

  /// ==============================
  /// START PAYMENT
  /// ==============================
  Future<void> startPayment({
    required double amount,
    required String description,
    required BuildContext context,
  }) async {
    _context = context;
    isProcessing = true;
    notifyListeners();

    logSafe("🟢 Starting payment for ₹$amount - $description");

    // Call backend to create Razorpay order
    final result = await _paymentService.createOrder(amount);

    if (result == null) {
      _showError(context, "Failed to connect to server.");
      isProcessing = false;
      notifyListeners();
      return;
    }

    final orderId = result['orderId'];
    final key = result['key'];

    if (orderId == null || key == null) {
      _showError(context, "Invalid response from server.");
      isProcessing = false;
      notifyListeners();
      return;
    }

    var options = {
      'key': key,
      'amount': (amount * 100).toInt(), // Razorpay takes amount in paise
      'name': 'Your Company Name',
      'description': description,
      'order_id': orderId,
      'theme': {'color': '#0D47A1'},
      'timeout': 120, // 2 minutes timeout
    };

    try {
      logSafe("🟠 Opening Razorpay with options: $options");
      _razorpay.open(options);
    } catch (e) {
      logSafe("❌ Error opening Razorpay: $e", level: LogLevel.error);
      _showError(context, "Error opening payment gateway.");
      isProcessing = false;
      notifyListeners();
    }
  }

  /// ==============================
  /// EVENT HANDLERS
  /// ==============================
  void _handlePaymentSuccess(PaymentSuccessResponse response) async {
    logSafe("✅ Payment Success: ${response.paymentId}");

    isProcessing = true;
    notifyListeners();

    final result = await _paymentService.verifyPayment(
      paymentId: response.paymentId!,
      orderId: response.orderId!,
      signature: response.signature!,
    );

    isProcessing = false;
    notifyListeners();

    if (result != null && result['verified'] == true) {
      _showDialog(
        title: "Payment Successful 🎉",
        message: "Your payment was verified successfully.",
        success: true,
      );
    } else {
      _showDialog(
        title: "Verification Failed ❌",
        message: "Payment completed but could not be verified.",
        success: false,
      );
    }
  }

  void _handlePaymentError(PaymentFailureResponse response) {
    logSafe("❌ Payment Failed: ${response.message}");
    isProcessing = false;
    notifyListeners();

    _showDialog(
      title: "Payment Failed ❌",
      message: "Reason: ${response.message ?? 'Unknown error'}",
      success: false,
    );
  }

  void _handleExternalWallet(ExternalWalletResponse response) {
    logSafe("ℹ️ External Wallet Used: ${response.walletName}");
  }

  /// ==============================
  /// HELPER DIALOGS / SNACKBARS
  /// ==============================
  void _showDialog({
    required String title,
    required String message,
    required bool success,
  }) {
    if (_context == null) return;

    showDialog(
      context: _context!,
      builder: (ctx) => AlertDialog(
        title: Text(title),
        content: Text(message),
        actions: [
          TextButton(
            child: const Text("OK"),
            onPressed: () {
              Navigator.of(ctx).pop();
              if (success) {
                Navigator.of(_context!).pop(true); // Return success
              }
            },
          ),
        ],
      ),
    );
  }

  void _showError(BuildContext context, String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(content: Text(message), backgroundColor: Colors.red),
    );
  }
}